The present invention relates to a front sprocket wheel having a chain guard for use in bicycles for driving the rear wheel of the bicycle through a chain.
Front sprocket wheels having a chain guard are known for use in bicyles wherein an inner gear, an outer gear diametrically larger than the inner gear and the chain guard larger than the outer gear are arranged concentrically with the pedal crankshaft of the bicycle and spaced apart from one another axially of the crankshaft. The inner gear, the outer gear and the chain guard, each of which is an independent annular member, are fixed to the crankshaft by a boss member having radial arms. The boss of the boss member is secured to the crankshaft, while the gears and the chain guard are spaced apart by predetermined distances and attached to the radial arms with use of collars.
Accordingly the conventional front sprocket wheel is cumbersome to assemble, costly and moreover heavy in its entirety.